The reason Tom and Shiv's marriage never worked out is because they wanted it to be about love when in reality it was not.
Shiv married Tom cause she thought he would be the perfect servant to always have her back.
Tom married Shiv cause he thought he would get an ally, an equal to share power with.
Love was never in the equation. And it's not that they are incapable of love, they're just not capable of loving each other.
And now that they cleared the air, now that everything is out in the open they can finally make their marriage work. Because the emotional connection is there. It might not be love but it is still strong and it is still worth it imo.
glad i had someone to tell me "dont watch the new yakuza trailer, it spoils too much but the coolest thing is that kiryu does a limit break and turns the turn based rpg back into an action game"